Wireless communication systems, for example cellular telephony or private mobile radio communication systems, typically provide for radio telecommunication links to be arranged between a plurality of base transceiver stations (BTSs) and a plurality of subscriber units, often termed mobile stations (MSs). Base station contollers (BSCs) are provided, each BSC controlling one or more BTS.
Wireless communication systems are distinguished over fixed communication systems, such as the public switched telephone network (PSTN), principally in that mobile stations move between BTS (and/or different service providers) and in doing so encounter varying radio propagation environments.
In a wireless communication system, each BTS has associated with it a particular geographical coverage area (or cell). A particular range defines the coverage area where the BTS can maintain acceptable communications with MSs operating within its serving cell. Often these cells combine to produce an extensive coverage area.
Present day communications systems, both wireless and wire-line, have a requirement to transfer data between communications units. Data, in this context, includes speech communication. Such data transfer needs to be effectively and efficiently provided for, in order to optimise use of limited communication resources.
One such wireless communication system is the third generation partnership project (3GPP) standard supporting wide-band code-division multiple access (WCDMA) relating to the Universal mobile telecommunication system (UMTS) radio access network (RAN) known as UTRAN. The European Telecommunications Standards Institute (ETSI) is defining the 3GPP standard.
Within UMTS nomenclature, the base transceiver station (BTS) is called a node B, and a base station controller (BSC) is called a radio network controller (RNC).
Within the UTRAN, many communication resources need to be managed effectively, for example:                (i) The air interface (i.e. CDMA power and code) resource, with separate air interface resources for, say, each cell.        (ii) The backhaul resource supporting, for example limited capacity E1 links, with separate resources for, say, each Node B.        (iii) Node B hardware/software resources, for example managing the Node B's processing capability (e.g. as defined by the microprocessors, back-plane networking, etc.), may limit the throughput of data that is achievable within a cell.        (iv) RNC Hardware/software resources.        
In some conventional systems, the same (or at least a similar) set of QoS management algorithms must be applied to each resource. These QoS management algorithms include:                (i) Admission control: performed when a new call enters the system/cell. Admission control has an objective of determining whether QoS will be maintained for all connections, if the new call is admitted.        (ii) Scheduling: performed every frame. Scheduling has an objective of ensuring that the number of data packets submitted for transmission will not exceed the capacity available over a short time period, such as a 10 msec. frame.        (iii) Overload control: used if the aforementioned admission control and/or scheduling mechanisms fail in their function, in order to rectify the situation. Actions might include ‘call pre-emption’ in which low priority calls are thrown off the system.        (iv) Flow control: This could be considered a sub-category of overload control, and is at least related to overload control. Flow control causes the source rate to be decreased in order that the system does not become congested.        
Running all four of these QoS control mechanisms, for each of the many UTRAN resources, consumes a significant amount of processing power in terms of mega instructions per second (MIPS). The processing impact is felt principally in the radio network controller (RNC) in the 3GPP system, but also in the Node B.
The inventors of the present invention have recognised and appreciated that current QoS management algorithms address all resources with equal regard. Hence, there is no consideration as to their relative importance in limiting the data throughput of the network. It is possible that in some, perhaps even most, instances, a few of the UTRAN resources will be over-dimensioned with respect to the others. For these (relatively speaking) over-dimensioned resources, the MIPS consumed in performing the QoS management functions will be wasted, since other resources will represent a bottleneck in limiting a data throughput performance.
Thus, there exists a need in the field of this invention, to provide an improved QoS management methodology, particularly in cellular base-site resources in a wireless communication system (where transmission delay is a constraint), wherein the abovementioned disadvantages may be alleviated.